Correspondence /3 5w r kf
February 14, 2006
CITY OF TIGARD
OREGON
A -1 S.S Fabco
PO Box 605
Oregon City, OR 97045
RE: MECHANICAL — EXHAUST DUCT SYSTEM FOR TYPE I HOOD
Project Information
Building Permit MEC2006 -00079 Construction Type: 5B
Tenant Name: NV House Occupancy Type: B
Address: 11305 SW Pacific Hwy Occupant Load: unk
The plan review was performed under the State of Oregon Mechanical Specialty Code (OMSC) 2004
edition. The submitted plans are approved subject to the following.
1. Provide automatic fire suppression systems for to type 1 hood prior to final inspection.
"Automatic fire suppression systems, including pre - engineered and engineered dry- and
wet - chemical fire- suppression systems shall be listed and labeled for specific use as protection for
commercial cooking operations and shall be installed in accordance with Section 304.1." OMSC
509.2
2. Type I hoods shall be secured in place by non- combustible supports. All hood supports shall be
adequate for the applied load of the hood, the unsupported ductwork, the effluent loading, and
the possible weight of personnel working in or on the hood. 507.6 OMSC
3. A Type I hood shall be installed with a clearance to combustibles of not less than 18 inches. This
clearance may be reduced to 3 inches, provided the combustible material is protected with
materials as specified for one -hour fire- resistive construction on the hood side. Hoods less than
12 inches from the ceiling or wall shall be flashed solidly with materials of the thickness specified
in Section 508.2 or materials conforming to one -hour fire- resistive construction. 507.9 OMSC
4. Makeup air shall be supplied during the operation of commercial kitchen exhaust systems. The
amount of makeup air supplied shall be approximately equal to the amount of exhaust air. For
mechanical makeup air systems. the exhaust and makeup air systems shall be electrically
interlocked to insure that makeup air is provided whenever the exhaust system is in operation.
Makeup air intake opening locations shall comply with Sections 401.5 and 401.5.1.
508.1 OMSC
5. The temperature differential between makeup air and the air in the conditioned space shall not
exceed 10oF (6oC).
Exceptions:
13125 SW Hall Blvd., Tigard, OR 97223 (503) 639 -4171 TDD (503) 684 -2772
1. Makeup air that is part of the air- conditioning system.
2. Makeup air that does not decrease the comfort conditions of the occupied space.
508.1.1 OMSC
• 6. Manufacturers of compensating hoods shall provide a label indicating minimum exhaust flow
and /or maximum makeup airflow that provides capture and containment of the exhaust effluent.
508.2 OMSC
7. Duct- to- exhaust fan connections shall be flanged and gasketed at the base of the fan for
vertical discharge fans; OMSC 506.3.2.3
8. Duct systems serving a Type I hood shall be constructed and installed so that grease cannot
collect in any portion thereof, and the system shall slope not less than one - fourth unit vertical in
12 units horizontal (2- percent slope) toward the hood or toward an approved grease reservoir.
OMSC 506.3.7
9. Equipment and appliances shall be installed as required by the terms of their approval, in
accordance with the conditions of the listing, the manufacturer's installation instructions and this
code. Manufacturer's installation instructions shall be available on the job site at the time of
inspection. OMSC 304.1
10. The building or structure shall not be weakened by the installation of mechanical systems. Where
floors, walls, ceilings or any other portion of the building or structure are required to be altered
or replaced in the process of installing or repairing any system, the building or structure shall be
left in a safe structural condition in accordance with the Building Code. The cutting, notching and
boring of framing members shall comply with OMSC 302 Sections 302.3.1 through 302.5.3.
11. Equipment and appliances regulated by this code requiring electrical connections shall have a
positive means of disconnect in accordance with the Electrical Code. 301.7 OMSC
12. Appliances shall be accessible for inspection, service, repair or replacement without removal of
permanent construction. 306.1 OMSC
Approved Plans: 1 set of approved plans, bearing the City of Tigard approval stamp, shall be
maintained on the jobsite. The plans shall be available to the Building Division inspectors
throughout all phases of construction. 106.4.2 OSSC
When submitting revised drawings or additional information, please attach a copy of the enclosed
City of Tigard, Letter of Transmittal. The letter of transmittal assists the City of Tigard in
tracking and processing the documents.
Rep ectfull
al He e,
Senior Plans Examiner